There is a variety of applications that utilize tubes, or a bundle of tubes for delivering or extracting liquid, gas, etc. A few non-limiting examples of such applications are seen in systems such as typical plumbing environments, large-scale plumbing environments, heat exchangers, reactors, boiler systems, etc. More particularly, one can typically observe the use of heat exchangers in systems such as power stations, refineries, chemical plants, air conditioning systems, etc. In applications that employ the use of such tubing for the transfer of liquid, the fluid flowing through the tubes may result in the facilitation of an accumulation of deposits on the inner surface of the tubes. The accumulation of such deposits results in degrading the efficiency of the tube and/or bundle of tubes. The accumulation in such environments may depend on a variety of circumstances, such as the ambient temperature of operation, the contents of the liquid, the flow rate, the flow volume, the type of material used in fabricating the tubes, the shape of the tubes (straight or bent), the size of the inner diameter, etc. As such, the accumulation of deposits on the inner surface of the tube(s) can occur at a variety of rates ranging from gradual to rapid accumulation. The accumulation of the deposits within the interior of the tube and/or tubes can have an adverse effect on the operation of the system utilizing the tubes. For instance, the accumulation may result in the reduction of heat transfer, reduction in the ability to cool a system or simply an obstruction of flow. Therefore, it is common practice in the maintenance of such systems to clean out the tubes periodically. The cleaning process is complicated by the fact that some deposits, for example scale, can be very hard to remove. To successfully clean and maintain the tubes, the cleaning process often involves several cleaning stages for the successive removal of such deposits.
Measuring the effectiveness of the cleaning process at the end of each stage and/or at the conclusion of the process is a difficult task. There are a few known methods for evaluating the cleaning. The most common method is to examine the tubes visually using a borescope. However, using a borescope in a bundle of tubes is very time consuming. In addition the borescope can only be used in the examination of straight tubes. Furthermore, the results of the evaluation using a borescope are objective and depend greatly upon the capabilities, judgment, opinions and the current condition of the user conducting the evaluation.
It should also be appreciated by those of ordinary skill in the art that the methods utilized in the current state of the art suffer from several deficiencies, such as but not limited to, the amount of time required in performing the evaluation, the dependency on the operator, the limitation of not being used in bundles of curved tubes, etc.